The invention concerns a connector for the construction of hollow tube mounting frameworks for electrical communications engineering, especially data processing engineering, and wherein at least two connection pieces are employed at a knot or point of intersection. These connection pieces are provided with adhesion grooves which are provided in the hollow tubes and are glued together thereby.
The previously known frameworks or structures consist of rectangular tubes which are welded together with one another. Nevertheless, welding has the disadvantage that because of the heat which arises, the frameworks become warped. Simultaneously, the metal coating which inhibits corrosion is damaged. A further disadvantage of the welding method is that in the case of a zinc-chromatized surface, during welding poisonous vapors arise. Besides this, the welding requires an expensive after-treatment because of the burnt welding zones.
For this reason, it is already known to glue together the individual rectangular tubes at their corners via so-called corner knots (corner points or intersection). These corner knots or junctions thereby represent connectors which have a point of intersection from which, for example, three connection pieces which lie perpendicular to one another extend. They preferably consist of metal, for example, of aluminum. These corner knots are then inserted into the hollow tubes and are glued together with ease. Therefore, adhesion grooves which encircle the connection piece surfaces are provided which are connected with one another via two longitudinal grooves. With spraying-in of the adhesive, first the adhesion groove fills, and only thereafter does the adhesive move into the adhesion crevice from all sides. The air is thereby trapped upon the adhesion surface and approximately 30% of the adhesion surface remains without moistening, or respectively, without adhesive filling. The adhesive connection must therefore be designed larger, that is, the leg length of the individual corner knots must be enlarged.